Latest news with #UniversityOfTokyo
Gizmodo
4 days ago
- Science
- Gizmodo
Origami Space Planes Could Solve a Major Problem in Orbit
Building a spacecraft could one day be as simple as folding a piece of paper into a plane and letting aerodynamics do the rest. A team of researchers from the University of Tokyo simulated the release of a paper airplane from the International Space Station (ISS) to see if would survive atmospheric reentry. In a paper published in Acta Astronautica, the researchers demonstrated how origami may be the solution to low Earth orbit's growing trash problem. Rather than relying solely on metals to construct spacecraft, the team behind the paper argues that a standard sheet of paper could do the job instead and easily burn up in the atmosphere during reentry. For their study, the researchers created a paper plane with an aluminum tail and placed it in a wind tunnel to see how it would fare in space. The idea is simple, and it aims to show how organic materials can be used to create a more sustainable orbital environment. The origami space plane is made from a sheet of uncoated A4 printing paper, with folded layers at the nose to shift its center of mass upstream and ensure aerodynamic stability. 'Such spacecraft have not yet flown in space,' the paper reads. 'It is unclear whether their flight dynamics in the highly rarefied atmosphere in [low Earth orbit] would be similar to those of a usual ground-based origami plane, and whether the plane would survive or burn up during atmospheric entry.' Of course, the entire spacecraft wouldn't be made solely of paper. Instead, specific components—like a wing or drag sail—could be constructed from paper-based materials. To test it out, the researchers first created a simulation of the paper plane being launched from the ISS at an altitude of 248 miles (400 kilometers) and a speed of 17,448 miles per hour (7,800 meters per second). The paper plane remained stable and glided through the space-like conditions. It began to tumble at a lower altitude of 74 miles above Earth's surface (120 kilometers) and spun out of control. The tumbling motion is expected at this altitude, and the severe aerodynamic heating would result in the paper plane burning up in the atmosphere at around 55 to 58 miles (90 to 110 kilometers) altitude, according to the paper. The researchers then placed a physical model in the Kashiwa Hypersonic and High Enthalpy Wind Tunnel at the University of Tokyo to see how it would hold up during reentry conditions. They subjected it to Mach 7 speeds for about seven seconds, during which the plane's nose bent and the wings showed signs of charring. It didn't fully disintegrate, though, but it most likely would have had they kept it in there for a longer period of time, the researchers said. Upon atmospheric reentry, traditional spacecraft leave behind metallic particles and chemicals that damage the ozone layer. The paper plane, on the other hand, is made of organic material that doesn't pose an environmental threat. Still, there are some challenges that remain. Considering how small the paper plane is, it does not reflect radar strongly enough and would be hard to track in orbit. The researchers suggest equipping it with a miniaturized position, navigation, and timing transceiver. It's also extremely sensitive to aerodynamic drag and therefore can only spend so much time in orbit, so it can be used for short-duration missions with small payloads. The origami space plane will likely not be a good fit for a wide range of missions, but the researchers suggest a version of it could be used as a passive probe to measure atmospheric density or as a platform for low-cost and short-lived missions in low Earth orbit. 'Owing to the extremely low cost of a paper space plane, multiple deployments could be conducted at the same time, and repeated at regular intervals, providing simultaneous distributed measurements,' the scientists explained in their paper. The idea of a childlike space plane gliding through the atmosphere may seem too simple, but using paper on spacecraft could help us resolve the overpopulation of metal crowding low Earth orbit and disintegrating into chunks of space scrap.
Japan Times
15-07-2025
- Health
- Japan Times
Japanese scientists discover clue to why women burn more fat than men
A team of researchers in Japan has discovered a key biological reason that may help explain why women tend to burn more calories from fat than men, a finding that could help pave the way for new treatments for obesity and related diseases. The study, published Monday in the journal Nature Communications, was led by researchers at the Institute of Science Tokyo in collaboration with the University of Tokyo. While men typically have a high proportion of muscle that helps them burn more calories in total, recent studies have shown that women burn more calories from fat specifically. For this study, the team focused on brown adipose tissue (known as BAT), a special type of fat in the body that burns energy to produce heat. Previous studies have shown that women have more active BAT than men and are less likely to develop Type 2 diabetes or other metabolic disorders. But until now, the reason behind this difference was unclear. Using mice, the researchers found that a protein called PGC-1alpha plays a key role in boosting calorie consumption in females. The protein helped power up mitochondria — the parts of cells that turn nutrients into energy, commonly referred to as the powerhouse of the cell — in their bodies by encouraging the production of specific fats that support mitochondrial function. The result was more energy burned as heat. When the scientists removed the PGC-1alpha protein, female mice showed a sharp drop in mitochondrial performance and calorie-burning ability, while male mice were largely unaffected. This suggests that PGC-1alpha works in a female-specific way to enhance fat metabolism. The study also revealed that estrogen, the primary female sex hormone, works together with PGC-1alpha to activate genes involved in fat processing. In female mice, this combination triggered higher levels of key molecules that help BAT burn calories. By mapping these differences at the molecular level, the researchers were able to show that women may have a built-in advantage when it comes to energy expenditure linked to both hormones and genetic regulators. While the current findings are based on animal models, scientists say the results could help explain why women are typically less prone to weight-related conditions and may lead to new therapies that target calorie-burning mechanisms. 'The findings of this study provide a new understanding of sex differences in energy metabolism,' the team said in a statement. 'This is a breakthrough achievement ... that could help elucidate mechanisms of obesity and contribute to the development of new methods and drugs to restore metabolic health.'
The Sun
09-07-2025
- General
- The Sun
Inside DOOMED Mt Vesuvius villa destroyed by volcano blast where famed Roman emperor may have died 2,000 years ago
THE luxurious but tragedy-stricken villa where the first Roman emperor, Augustus, is believed to have died has been unearthed after 2,000 years. Researchers from the University of Tokyo say there are a number of clues that suggest the posh villa belonged to Augustus, who lived between 63 BC and 14 AD. 5 5 5 The 3,650-square-meter villa located at Somma Vesuviana, at the northern foot of Mount Vesuvius, was destroyed on the day of the eruption in 79 AD. The famous buried city of Pompeii was located on the mountain's southern slope, and was also completely destroyed by the same eruption. The ruins of the villa, which were buried under a thick layer of volcanic ash, reveal luxuries only afforded to the ultra-wealthy at the time - namely, a private bath. It boasts five large furnaces, which are presumed to have heated an enormous bath. That number of furnaces has been called an exceptionally rare find by the archaeological community. Carbon found inside the furnace dates back to around the first century, and suggests they went cold not long after. "There has never been a case where five large furnaces have been excavated from an Italian site," Mariko Muramatsu, professor of Italian studies at the University of Tokyo, said. 5 Muramatsu, who began an archaeological survey of the site in 2002, added: "It makes sense as an explanation that no one else but the emperor could make such a magnificent feat possible." The researchers noted that Augustus, who held immense power as the founder of the Roman Empire, may have used the building as a guesthouse. That many furnaces would have heated a significant amount of water, which may have even been used to entertain influential guests. "It is almost certain that they were used to heat a large amount of water for a huge bath facility," said Masanori Aoyagi, former commissioner of the Agency for Cultural Affairs and professor emeritus at the University of Tokyo. The researchers also said the bath was out of use around the same time Augustus died in 14 AD, and what appeared to be a large temple was later constructed on the site. 5 Augustus' grave has never been found, but ancient records say he passed away at his villa northeast of Mount Vesuvius. Accounts from that period also say a memorial was built there in memory of his accomplishments - but the precise location of that villa has remained a mystery. Despite the lack of conclusive evidence, researchers say another clue supporting their theories is the fact that the site is located more than 200 kilometres from Rome. "Augustus built a guesthouse with a huge bath beyond Roman citizens' scrutiny in a bid to show his greatness to aristocrats and military officers and have them feel the Pax Romana (Roman peace) in the bath," said Aoyagi, who served as the first project head of the research team. The research team has already begun excavations on the south side of the furnace in hopes of finding the remnants of ancient bath water. A brief history of the Roman Empire Here's what you need to know... The Roman Empire began shortly after the founding of the Roman Republic in the 6th century BC It reigned for around a thousand years until the fall of the last Western emperor in 476 AD During this time, the Romans ruled over many countries in Europe and parts of Africa and the Middle East At its height, 90 million people lived in the Roman Empire It evolved from a monarchy to a democratic republic to a military dictatorship and then was finally ruled by emperors One of the most well-known Roman leaders is Julius Caesar, famously assassinated in 44BC He is largely credited for his military mind and laying the foundations for the Roman Empire The spread of the Roman Empire into Britain in around 55 BC has had a lasting impact on our lives today Latin, straight roads, underfloor heating and the spread of Christianity are all attributed to the Romans
The Guardian
04-07-2025
- Science
- The Guardian
Cramps, fatigue and hallucinations: paddling 200km in a Paleolithic canoe from Taiwan to Japan
Dr Yousuke Kaifu was working at an archaeological site on the Japanese islands of Okinawa when a question started to bubble in his mind. The pieces unearthed in the excavation, laid out before him, revealed evidence of humans living there 30,000 years ago, arriving from the north and the south. But how did they get there? 'There are stone tools and archaeological remains at the site but they don't answer those questions,' Kaifu, an evolutionary anthropologist at the University of Tokyo, says. In the Paleolithic era, or the old stone age, technology was rudimentary, he says. 'I thought it was great they reached those islands with such simple technology. I wanted to experience it.' So Kaifu devised an adventurous plan that would see a team of researchers take to the sea in a 225km canoe trip from Taiwan to Japan's Yonaguni island. Yonaguni is the closest of the Ryukyu islands – a chain stretching south-west from Kyushu to Taiwan – but it lies across one of the world's strongest currents. The voyage was reminiscent of the famed 1947 Kontiki crossing by Norwegian Thor Heyerdahl, which proved it was possible that peoples from South Americas paddled to Polynesia. But first, Kaifu's team needed a boat. Any vessel used by the original Paleolithic travellers had long since disintegrated. The team used traditional techniques to build rafts made of bamboo and reed, but ocean tests found they were too slow to battle the Kuroshio current, which was even stronger at the time of the Paleolithic crossing. 'Through those failed experiments we gradually learned the difficulty of the crossing, but at the same time we knew the Palaeolithic people were on the island. They had succeeded, so there must be a resolution which we just hadn't found,' Kaifu says. Eventually, the team built a heavy, unstable but workable dugout canoe out of Japanese cedar, and identified Wushibi bay on Taiwan's east coast from which to launch the 'Sugime'. Crucially, Yonaguni is not visible from Taiwan's shore but can be seen on a clear day from its mountains, near Taroko. The researchers believed it likely that the early migrants had seen it, and that they were well aware of the strength and behaviour of the Kuroshio current from fishing ventures. The team of five included professional paddlers as well as the scientists, but no one who had made such a journey, let alone without modern navigation. The day they set out, the weather was not good, Kaifu recalls, with choppy seas and clouds obscuring the stars they needed to find their way. Instead, they had to rely on another ancient technique, monitoring the direction of the swell to keep their own direction stable. 'Polynesian and Micronesian people did it, and we learned the technique,' says Kaifu, who travelled on the crew's escort vessel, 'the safe place', he laughs. For 45 hours they paddled, suffering muscle aches, fatigue, cramps and even hallucinations. 'Surrounded only by the sea, clouds, and sky, they were uncertain about their position,' the report's journey log notes. But their arrival on the second night was anti-climactically untraditional. Still almost 40km away, 'they found the island by the lighthouse, which was unfortunate', Kaifu said. 'But the beautiful moment for me was the time of [the previous day's] dawn, the sun was coming up and the sky became gradually light, and we saw the clouds on the horizon. But at one point on the horizon the clouds were different, so there must be something under the clouds. That was the moment we were sure the island was there. Just like the ancient people, the ancestors, it was good to capture the island from the natural signature.' The team made the journey in 2019, with support from Japan's National Museum of Science and Nature, Taiwan's National Museum of Prehistory, and crowdfunding donors. Last week they published two papers and a 90-minute documentary on their findings, on the journey itself and on the ocean modelling of the route's treacherous currents and unpredictable weather. 'Paleolithic people are often regarded as 'inferior' among the general public, primarily due to their 'primitive' culture and technology,' the report said. 'In sharp contrast, our experiment highlighted that they accomplished something extraordinary with the rudimentary technology available to them at the time.' There is much unknown about the early migration of humans. Homo sapiens are believed to have spread across the world with large-scale maritime expansion occurring at least 50,000 years ago. A 2017 study in northern Australia found it could have been 15,000 to 30,000 years earlier than that. The team's report noted growing consensus in the scientific community that the maritime migrations were driven by intentional seafaring more than accidental drifting, but without really knowing much about how. Kaifu's team found that while the journey from Taiwan to an unseen island was treacherous and required skill, strength and a lot of luck, it was possible. Almost six years to the day since his team paddled away from Wushibi, Kaifu is excited recalling the details of their 'imperfect' journey. 'We anthropologist and archeologists who have studied human migration in the past, we draw a line on a map,' Kaifu said. 'But behind each of those lines there must be a great story. Crossing the ocean can't be represented by a simple line. I wanted to know the real story behind those migrations.'
Japan Times
04-07-2025
- Business
- Japan Times
Japan's inflation is outpacing BOJ's view, expert says
Japan's inflation is surprisingly strong, increasing the possibility that the Bank of Japan will raise its interest rate by the end of the year, according to one of the country's leading inflation experts. "It's beyond my expectation and very strong this year,' said Tsutomu Watanabe, an emeritus economics professor at the University of Tokyo, in an interview Friday. "There is no mistake that the BOJ will raise its forecast for this fiscal year' in its quarterly outlook report at the end of the month. Watanabe's remarks are likely to feed market expectations for another interest rate hike this year. The latest government data showed the cost of living re-accelerating to a fresh two-year high in May, although BOJ Gov. Kazuo Ueda has made it clear that he wants to confirm the level of economic impacts from U.S. tariffs in data before moving the rate again. "A rate hike could take place at the end of this year or early next year,' Watanabe said. "Japan's price growth is probably coming into the danger zone' for the central bank to fall behind the curve, as businesses continue to pass their costs on to consumers, he said. Japan's cost of living is rising at the highest rate among Group of Seven countries, with the May data registering 3.7% for the country's key price gauge. Ueda has defended his gradual approach by saying that the underlying price trend is still slightly below 2%, a view that Watanabe disagreed with. At the same time, Watanabe supported the BOJ's stance of carefully studying data on inflation and the impact of tariffs. For inflation, the price of rice has been a driving factor and it's unclear how much it will go down due to ongoing measures from Prime Minister Shigeru Ishiba's administration, he said. The price of Japan's staple food has roughly doubled this year, garnering national attention and resentment. The effects of a trade deal are expected to show up in data around this fall, so the BOJ could judge whether a rate hike is justified toward the end of this year, as the central bank parses the inflation trend, according to Watanabe. Watanabe is a former BOJ official and was in a shortlist of potential candidates in 2023, along with Ueda, for central bank governor, according to some reports. The economist admitted that the current strength of inflation is a surprise for him, after he repeatedly criticized Ueda's rate hikes because the price momentum wasn't firm enough to back up the move. The BOJ delivers its next policy decision on July 31 when more than 90% of BOJ watchers expect the rate to be left at 0.5%, according to a survey last month. With little expectation of a policy change, the bank's updated quarterly outlook will be a key focus among traders. The BOJ currently forecasts core inflation to rise 2.2% in the year ending in March, and 1.7% the following year. "There will be a slight upward revision for this year,' Watanabe said. "But the BOJ will probably show it's below 2% in the following year to say it has to proceed cautiously.'
